An anti-government protester joins others blocking the road at one of major intersections in central Bangkok, on Jan. 13. See more images here.

Antigovernment protesters are taking to the streets of Bangkok today during mass rallies aimed at putting pressure on Prime Minister Yingluck Shinawatra to leave office. Major intersections have been closed to traffic and crowds started gathering on Sunday night in preparation for a day of demonstrations they’ve dubbed the “Bangkok Shutdown.” Here’s where they’ll be gathering. Follow Southeast Asia Realtime for on-the-ground updates.

Protesters who camped out over night in front of Central World shopping mall along Rachadamri Road in central Bangkok start waking up. A stage set up at the intersection blasts loud dance music and people begin arriving in t-shirts emblazoned with the words, “Bangkok Shutdown.”

At the MBK rally site, two men regale the crowd with a pep talk, drawing cheers and whistles. People sit on mats on the road and sidewalks. The gathering is still not too dense. Many of those present have clapper toys that they use as noise makers to show applause.

There are few people at Nonthaburi pier, outside Bangkok’s city center. The boat service that runs there provides a connection to mass transit, like the BTS skytrain. A group of passengers, employees at Ratchadamnoen Bank, say they’ve decided to not to drive into the city today to avoid traffic snarls. Some of them say it’s the first time they’ve taken this type of public transportation. The fare for the boat has been reduced to accommodate passengers making their way to work. Some people have opted to work from home to avoid protest traffic.

Protesters surrounded part of Victory Monument, one of the main protest sites in Monday’s rallies. A speaker on stage plays the national anthem and those gathered stand and sing together. Main thoroughfares and major bus stops in Bangkok are seeing significantly less traffic from outer areas. There are not many passenger cars — only buses, motorcycles and commuter vans.

“There are fewer passengers today, people feel insecure about going out,” says a motorcycle taxi driver. The streets near Ladprao intersection are nearly empty, which is unusual on a Monday morning. Schools are closed. “It’s like a long holiday when people leave to go up-country,” the driver says.

Commuters taking the San-Saeb boat service that runs from Bangkok’s outskirts to its center disembark at stops close to the subway and airport link. Sangdauen Noptakol, an officer from the Family Transport Company, which runs the service, estimates that the number of passengers boarding and getting off to make connections has increased by 30%.

Protesters carrying Thai national flags of all sizes continue to walk toward the main stage at the Ratchaprasong intersection. Passenger vans and pick-up trucks block the road from Pratunam intersection, north of Ratchaprasong Road.

“I don’t like Yingluck’s government and her populist policies,” says Donnapa Anupongmaneerat, 48, a business owner who traveled from Chonburi province in the east this morning to join her friends at a rally site in Asoke.

”I’ve joined every major rally,” she says. “I don’t think Yingluck will give up easily even though we’ve come out many times. She has no shame. But we’ll not give up. We’ll keep coming out.”

According to local news reports, General Prayuth Chan-Ocha, the chief army commander, and other armed-forces’ leaders are planing to hold a meeting on the Bangkok shutdown. No further details have been released.

Chumpol Jullasai, a former opposition lawmaker, calls on protesters gathered at Ratchaprasong stage to surround the National Police headquarters located next to the intersection to make sure its gates stay open.

Thousands of antigovernment protesters march from Ladprao intersection to the Ministry of Emloyment at Din Dang. They wave flags and blow whistles and horns. Meanwhile, another group of protesters arrive at Ladprao from Thailand’s noth and northeast, where Ms. Yingluck and the Shinawatras have their support base.

Thailand’s benchmark SET index opens at 1244.2, down 0.9% from its Friday close. Bangkok’s street unrest has spooked investors in recent weeks, prompting the market to fall almost 14% since protests began in early November. Among the larger companies losing value early Monday is 7-Eleven operator CP All PCL and Bangkok Bank PCL, which trade 1.3% and 0.9% lower. The SET was last down 0.3% at 1251.5.

Thanapong Kongwaree and around 100 other emergency workers arrive in Bangkok from Suratthani province in the south to provide first aid and assistance to protesters during Monday’s rallies.

Throughout the day Mr. Thanapong and his team will monitor the rally sites and make sure protesters are staying hydrated and healthy. He says they have first aid kits available to attend to any minor injuries.

Mr. Thanapong said he chose to be based at Ladprao intersection because the stage there is close to a key gathering site for the Red Shirts, a group that supports Prime Minister Yingluck and the Shinawatra family. Mr.Thanapong says he is worried that there might be a clash between the two groups.

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“I know this place is dangerous, so I told my colleagues to be in touch via radio all the time and not to leave their station at Ladprao intersection alone,” he said.

Protest leader Suthep Thaugsuban says he is heading up a “people’s revolution,” in brief interviews given to reporters as he marches with his supporters through Bangkok.

“We are doing it ourselves and we aren’t looking for help from the military. We are urging state employees to join us,” he says. “Our goal is to get rid of the Thaksin regime. Yingluck’s government is an important tool to the Thaksin regime, that’s why we have to force out her government.”

A gang of protesters ride motorcycles north along Ploenchit Road. They carry large Thai flags and blow whistles. One man holds up a picture of the King. The atmosphere is parade-like as protest leaders continue to rally their supporters from the stage at Ratchaprasong.

Thai army spokesperson, Col. Winthai Suvaree, tells a local television station that the army has not been working with the police on a crowd-control strategy but is offering first-aid services to the public. Thousands of military officers have also been stationed at key government offices and public utilities to provide secuirty, he said.

Thai police estimate that about 31,300 people were gathered at main rally locations in Bangkok as of 9:30 a.m. Monday. They say they will continue to update the number of protesters throughout the day.

Protest leader Suthep Thaugsuban makes his was to Ratchaprasong surrounded by thousands of supporters. He collects 100 baht bills and stuffs them into a bag. Some supporters guard Mr. Suthep by forming a human chain around him while those lining the street clap with excitement and pull him in for photographs.

The Thai government confirmed that it has no plan to impose a state of emergency after tens of thousands of protesters took the streets to shut down Bangkok: Deputy Prime Minister Surapong Tovichakchaikul.

Thailand’s benchmark stock index surges 2.2% to close at 1283.5, its highest level so far in 2014, as market sentiment gains from a peaceful day of protests.

After an early falls of as much as 0.9%, the Thai bourse gained strongly in afternoon trading. Among the best performers were telecoms provider Advanced Info Service PCL, which gained 4.9%, and Airports of Thailand PCL, which ended up 5.3%.

“We’ve had these [political] problems for many years now, and each time the economy—which is very resilient—and the companies bounce back,” said Adithep Vanabriksha, chief investment officer in Bangkok for Aberdeen Asset Management, which has around $6.2 billion invested in the country.

Mr. Adithep said as long as any new government was pro-business—which he considers likely—he didn’t see the current political tensions affecting investor sentiment too gravely. “It’s more the manner in which the government changes” that concerns investors, he said.

Despite the peaceful nature of Monday’s protets, some market analysts say Thailand will still be seen as a risk if the political impasse is prolonged or escalates to the point where the government ceases to function or is absent entirely.

“If you compare [it] to other emerging markets, Thailand has definitely fared worse and that’s due to the political unrest,” said Sutapa Amornvivat, chief economist at Thailand’s Siam Commercial Bank.

Thailand’s economy is already showing signs of slowing, and potential delays to planned infrastructure projects and foreign investment could further impede growth, she said.

Protesters remained on the streets Monday evening, as Suthep Thaugsuban addressed a crowd at Pathumwan stage in central Bangkok.

He called on protesters to intensify their battle against Ms. Yingluck every day until the government was toppled, claiming “only one side will win.”

“When we planned our operation to shut down Bangkok every day until we win, the government underestimated us,” said Mr. Suthep. “We will show the government that not only can we last for three days, we can last for 30 days or even three months.”

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